A few months ago I posted the pix below and asked what the herd thought it could be. I got a lot of responses from a gasket leak to normal condensation from short trips to a bad flux capacitor (not that because I replaced the flux cap just a week before).

I remembered seeing this condition before so I went with goo build up from short trips.

I use Mobil 1 5W-30 oil with a filter change at each oil change usual at about 6-7 K miles.

I went to Penzoil Platinum with NO changes in driving patterns and although no pix is included, the filler stayed clean as the day it was new.

Mobil 1 is good stuff but it does often show high iron when an oil analysis is done and it appears not to handle short trips as well as Penzoil.

mobil 1 sucks. Alot of people still praise it though its not a real true syn imho. I run Pennzoil Ultra in my 09 cts-v and that is most likely the best APPROVED oil on the market outside the amsoil products

I had the same problem. A friend told me it was because I took off the stupid plastic cover on top of the engine! I put it back on and cleaned all the crap out of cap and filler neck and it hasn't been back. That cover holds heat in and prevents that condensation. Has nothing to do with the oil.

It isn't the oil. That is from either a cracked head, or a leaking head gasket. I had the same problem due to switching from the old style antifreeze to the new style. It mixed because there was some left over in the heater core.

Pull your spark plugs and look inside the tubes and look at the spark plugs themselves.

Mobil one wont do this to your engine. Even though it is not a group 5 or whatever, it is still a good oil.

It isn't the oil. That is from either a cracked head, or a leaking head gasket. I had the same problem due to switching from the old style antifreeze to the new style. It mixed because there was some left over in the heater core.

Pull your spark plugs and look inside the tubes and look at the spark plugs themselves.

Mobil one wont do this to your engine. Even though it is not a group 5 or whatever, it is still a good oil.

I'm sorry but this is wrong. Mobil 1 does it, dyno does it too. It's because of two things; extended plastic fill tubes and no breathers.

40k on my 2010 and I have been using Mobil One for the past 5 or so oil changes. I do not have the engine cover either. I never get this stuff on the bottom of my 710 cap or in the neck itself. I drive 62 miles round trip for work 4 days a week.

Did you run an oil report through Blackstone (or some other lab)? I'd be interested in seeing the results.

Quote:

Originally Posted by tim455

I had the same problem. A friend told me it was because I took off the stupid plastic cover on top of the engine! I put it back on and cleaned all the crap out of cap and filler neck and it hasn't been back. That cover holds heat in and prevents that condensation. Has nothing to do with the oil.

Quote:

Originally Posted by Razorecko

mobil 1 sucks. Alot of people still praise it though its not a real true syn imho. I run Pennzoil Ultra in my 09 cts-v and that is most likely the best APPROVED oil on the market outside the amsoil products

Didn't go through Blackstone on this one.

Didn't take the plastic cover off. I feel it has a lot to do with the oil.

I think it was Casterol that started calling itself synthetic oil when in fact it is hydrocracked oil which is a super highly refined dino that exhibits synthetic properties. Mobil sued and lost in court. From that point on, there seemed to be a change in Mobil's formula that a lot of people questioned but got no answers to. They MAY have gone to hydrocracking as a cost saving and profitable measure now that hydrocracked oil could be peddled as synthetic.

as a former jeep nut i can tell you that this is caused by short trips and not fully heating the motor up. do you do mostly short trips? i doubt its a gasket blown or anything else. just wipe the crud out and keep an eye on it